| 摘要 |
<p>The present invention relates to a method of making a coated substrate that requires a polyurethane/urea contact adhesive, and the coated substrates produced by this method. This invention requires a) a polyisocyanate with a functionality of less than about 4, b) optionally, a polyol blend consisting of about 95 to 100% polyether polyols with molecular weights from about 1800 to 12000 and average functionality from about 1.5 to about 4 and up to about 5% of chain extenders with molecular weights from about 60 to 400 and average functionality from about 1.5 to about 3, and c) polyethers having at least two isocyanate reactive groups and a molecular weight of from about 1800 to about 12000 and average functionality from about 1.5 to about 4 in which at least 50% of the isocyanate reactive groups are primary and/or secondary amino groups. The weight ratio of components b) to component c) ranges from about 95:5 to about 0:100, and the amounts of components a), b), and c) are such that the equivalent ratio of isocyanate groups to isocyanate-reactive groups is from about 85:100 to about 115:100 and the sum of the urethane group content plus the urea group content is from about 1 to about 12%.</p> |
